XSS in Mybb
CVE-2019-12830
In MyBB before 1.8.21, an attacker can exploit a parsing flaw in the Private Message / Post renderer that leads to [video] BBCode persistent XSS to take over any forum account, aka a nested video MyCode issue.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.7 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.010 (60.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 60.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000
Affected products
Weakness classification (CWE)
References
- blog.ripstech.com/2019/mybb-stored-xss-to-rce/ (Exploit, Vendor Advisory)
- blog.mybb.com/2019/06/10/mybb-1-8-21-released-security-maintenance-release/ (Third Party Advisory, Release Notes)
Frequently asked questions
- What is CVE-2019-12830?
- CVE-2019-12830 is a high-severity vulnerability in Mybb, classified under Cross-site Scripting. CVSS score: 8.7/10. Published 2019-06-15.
- How severe is CVE-2019-12830?
- High severity. CVSS v3 base score is 8.7 out of 10.